Highly-brominated indigoes and process of making same.



I Ph. D., a citizen of the Empire of Germany,

ucts may be obtained.

ALBRECHT SlfHMIDl, Ol HCUHST-ON-THE-lllAlN, GERMANY, AS SIGNOR TO FARBWERKE STATES PATENT (n uron.

V ORM. MEISTER LUCIU S & BRUNING, OF I-IOCHST-ON-THE-IVIAIN, GERMANY, A CORPORA- 4 TlON OF GERMANY.

HIGHLY-BRQMINATED INDIGOES AND PROCESS OF MAKING SAME.

Application filed December 7. 1907. Serial Nc.'405,498.

T0 all whom concern:

Be it'known that I, ALBRECHT'SOHMIDT,

and residing at H6chst-on the-Main, Germany, haveinvented certain Improvements in Highly-Brominated Indigoes and Processes of Making the Same, of which the followingis a specification. 4

I have found that if di-halogenindigoes, for instance, di-bromindigo (obtained by brominating indigo) or for instance, di-chlorindigo (obtained from chloroanthranilic acids of.

known constitution) or for instance chlorbromindigo .(obtained by chlorinating indigo or iridigo-white with chlorin or with sulfurylchlorid and further bromination) be treated with an excess of bromin of at least two atoms of bromin above that quantity-0f bromin which is required for the tetrahalogenation in the cold or while gently heating", green-black, very highly brominated prod- When treated with agents capable of eliminating bromin, such, for instance, as bisulfite, said products lose part of the bromin, become blue whereby highly brominated dyes'tufls result which dye in the vat blue of a greener and clearer tint than the parent dyestuffs.

Example I: If di-bromindigo, obtained by di-brominating indigo, be stirred with an ex cess of liquid bromin,for instance, 2, 3 0rd times its weight of bromin, the di-bromin-digo turns, while gently heating, into a greed black product. It is insoluble in carbon tetrachlorid, benzene and .the like, pretty readily dissolved, however, byynitrobenzene to a darkgrecn solution. At ordinary temperature already it gradually gives up bromin, more readily on heating, whereupon it becomes blue. When treated with bisullite in the heat it also turns blue while losing bromin.

Example II: the mixture in Example I, for instance, a mixture, obtained from 10.

parts of di-bromindigo, 30 parts of bromin (with or without addition of 10 parts of phosphQroxy-chldrid)' be gently heated for instance-Iforsome time to 50-80" C. there is also obtained a greenish-black product of reaction, This still higher brominated product may be isolated. by stirring .it with carbon tetrachlorid, filtering and subsequent washing with carbon tetrachlorid. It contains bromin or bromin and "hydrogen bronnd Specification of Letters Patent.

Patented March 23, 1909.

lightly linked; it is green-black, insoluble in the usual solvents and dissolved by cold nitrobenzene partly to a dark green solution. At ordinary temperature it slowly gives up bromin, when heated with a solution of bisulfite the green-black mass turns into a blue.

paste of a highly brominated indigo which dissolves in concentrated sulfuric acid to a blue solution. The dyestui'i thus obtained dyes in the vat clear blue tints. In the manufacture of these green-black, highly brominated products, there may also be used zindifferent solvents in limited proportions,

such, for instance, as 08,, 001,. It is essential, however, that bromin predominates or that there be an excess of bromin of at least two atoms of bromin above that quantity of bromin which is required for the tetrahalo genation so that the green-black highly brominated products may form themselves.-

Exainple III: 30 parts of di-bromindigo from indigo are gently heated fora consider-' able time in a water-,bath in a reflux ap aratus with 80 parts of bromin, 50 parts 0 carbon tetrachlorid (with or without addition of some iodin or any of the known bromin carriers in the bromin substitution). The prodnot of reaction is diluted with carbon tetrachlorid, filtered and washed with carbon tetrachlorid. The green-black product thus" obtained has similar not in Example II.

properties as the prod- Example 1V: If the green-black products thus described be gently heated with neutral or feebly alkaline hydros'ulfites, for instance, with the equal proportion of sodium hydrosulfiteof 80 per cent.- strength in an aqueous feebly alkaline suspenslon, gray -greenish leuco bodiesare obtained which are insoluble in water, soluble in an alkali hydrate solution, dyeing cotton and wool from these solu-- tions blue.

If in the foregoing example for di-bromindigo be substituted di-chlorindigoes or chlorbromindigo, quite similar green-black prodnets are obtained which become blue with bisulfite, dyeing. in the vat clear blue tints.

Having now described my invention, what I claim is: y

l. The processiherein describcdoi making green black highly brominated products from di-halogenindigoos which consists in treating di-halogenindigoes with an excessof bromin of at least two atoms 'ol' bro min above that quantity of bronlin which is required for blo in water, soluble'in' an alkali-hydrate so the tetrahalogenation. lution, dyeing cotton and wool in these solu- 2. As new products the green-black highly tions blue. brominated products, being insoluble in car- 1 In testimony, that I. claim the foregoing as bon tetrachlorid, yielding with bisulfite blue dyestuffs, yielding with neutral hydrosulfite grz y-greenish leuco-coinpounds insoluble in water and soluble in alkali. Witnesses:

3. As new products, gray-greenish highly J EAN GRUND, 1O broniinated leuco compounds, being insolu- CARL GRUND.

my invention, I have signed my name in presence of two subscribing witnesses.

ALBREOI [T S( JHMI] )'I. 

